FROM nextcloud:fpm

RUN set -ex; \
    \
    savedAptMark="$(apt-mark showmanual)"; \
    \
    apt-get update; \
    apt-get install -y --no-install-recommends \
        libc-client-dev \
        libkrb5-dev \
    ; \
    \
    docker-php-ext-configure imap --with-kerberos --with-imap-ssl; \
    docker-php-ext-install imap; \
    \
# reset apt-mark's "manual" list so that "purge --auto-remove" will remove all build dependencies
    apt-mark auto '.*' > /dev/null; \
    apt-mark manual $savedAptMark; \
    ldd "$(php -r 'echo ini_get("extension_dir");')"/*.so \
        | awk '/=>/ { so = $(NF-1); if (index(so, "/usr/local/") == 1) { next }; gsub("^/(usr/)?", "", so); print so }' \
        | sort -u \
        | xargs -r dpkg-query --search \
        | cut -d: -f1 \
        | sort -u \
        | xargs -rt apt-mark manual; \
    \
    apt-get purge -y --auto-remove -o APT::AutoRemove::RecommendsImportant=false; \
    rm -rf /var/lib/apt/lists/*